Bearing and seal assemblies of the type to which the present invention relates generally include a seal member having both an angle ring forming a sealing gap, and a lamellar ring seal mounted between the angle ring and one of the bearing rings of a roller bearing or the bearing housing. Seal assemblies used to support the drive rolls of continuous casting machines are subjected to considerable thermal stresses and there is also the danger of contamination of these seals by exposure to coolant, steam, scale and other foreign matter.
Previous sealing devices have been proposed in an attempt to solve these problems, however none of them have proved as satisfactory as the present invention. For example, West German Patent No. 3,503,344 A1 shows a seal wherein the angle ring is mounted next to the bearing seating surface in the transition region between the neck of the roll and the roll itself. The angle ring has a shank which rest against the end surface of the roll and another shank which projects into the intermediate space between the inner ring of the bearing and the housing bore to form a sealing gap with the housing bore. The shank has a lateral surface which mounts a lamellar ring seal so that it engages in a peripheral groove in the bore of the housing. A shoulder with a ring shaped groove is provided in the transition region between the roll neck and the roll to provide a means for insuring that the angle ring remains fastened to the end surface of the drive roll. The angle ring is designed with an appropriate complementary shape to fit into this ring-shaped groove.
It has been found that the bearing and seal assembly described above is complicated and expensive to manufacture by reason of the special customized complicated shape needed for the drive roll. Furthermore, the surface in the contact area of the angle ring needs to be machined with great precision to guarantee a sealing effect between the angle ring and the roll or roll neck.
Furthermore, in solving the problem in this fashion, it is difficult to position the angle ring in a precisely concentric manner with respect to the outer ring of the bearing or the housing even though this concentricity is necessary for the formation of the sealing gap. This arrangement also has the draw back that the danger of breakage of the drive roll is increased because of the sharp-edged transitions which occur in the area of the shoulders producing a so-called "notch effect."